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牛蒡子(Arctii Frutus)是菊科植物牛蒡Arctium lappa L的干燥成熟果实,作为常用中药被收载于中国药典。牛蒡子具有辛凉解表、疏风散热和清热解毒的功效,用于风热感冒、咳嗽多痰和麻疹等症。对其初步的药理活性筛选表明其具有抗氧化和保肝活性,为了进一步阐明牛蒡子的药效物质基础,本论文采用多种色谱分离手段相结合的方法对牛蒡子乙醇提取物经乙酸乙酯萃取后的水部位中的化学成分进行了分离,共得到51个化合物,根据化合物的理化性质和光谱数据确定了它们的结构,包括18个新化合物,其中化合物1*是结构较新颖的木脂素类衍生物,其结构中具有一个较为罕见的6-羧基-α-吡喃酮片段,根据生源途径分析,该结构片段是通过3,4-二羟基苯环经氧化开环后,形成的4-氧代-2-羟基己酸片段中的醛基被再次氧化成酸后,通过分子内酯化反应关环形成了该结构片段。这51个化合物分别为：arctiidilactone(1*), (8R,7’R,8’R)-rafanotrachelogenin-4-O-β-D-glucopyranoside (2*), (8R,7’S,8’R)-rafanotrachelogenin-4-O-β-D-glucopyranoside (3*), (8R,7’R,8’R)-4,4’,7’-tri-hydroxy-3,3’-dimethoxy-9-oxo dibenzylbutyrolactone lignan-4-O-β-D-glucopyranoside (4), (7S,8S,8’R)-4,7-dihydroxy-3,3’,4’-trimethoxy-9-oxo dibenzylbutyrolactone lignan (5*), (7S,8S,8’R)-4,7-dihydroxy-3,3’,4’-trimethoxy-9-oxo dibenzylbutyrolactone lignan-4-O-β-D-glucopyranoside (6*), (7R,8S,8’R)-4,7-dihydroxy-3,3’,4’-trimethoxy-9-oxo dibenzylbutyrolactone lignan-4-O-β-D-glucopyranoside (7*),(7R,8S,8’R)-4,7,4’-trihydroxy-3,3’-dimethoxy-9-oxo dibenzylbutyrolactone lignan-4-O-β-D-glucopyrano-side (8*),arctigenin-4-O-α-D-galactopyranosyl-(1μ6)-O-β-D-glucopyranoside (9*), arctigenin-4-O-β-D-apiofuranosyl-(1→6)-O-β-D-glucopyranoside (10*),5’-propanediol-matairesinoside(11*), arctiinorlignan A (12*), matairesinol-4,4’-di-O-β-D-glucopyrano-side (13), arctiin (14), arctigenin-4-O-β-D-gentiobioside (15), styraxlignolide E (16), styraxlignolide D (17), (7S,8R)-4,7,9,9’-tertahydroxy-3,3’-dimethoxy-8-4’-oxyneolignan-9’-O-β-D-apiofuranosyl-(1→6)-O-β-D-glucopyranoside (18*), (8R)-4,9,9’-trihydroxy-3,3’-dimethoxy-7-oxo-8-4’-oxyneolignan-4-O-β-D-glucopyranoside (19*), (7R,8R)-4,7,9,9’-tertahydroxy-3,3’-dimethoxy-8-4’-oxyneolignan (20), (7R,8R)-7,9,9’-trihydroxy-3,3’-dimethoxy-8-O-4’-neolignan-4-O-β-D-glucopyranoside (21),(7R,8R)-4,7,9,9’-tetrahydroxy-3,3’-dimethoxy-8-O-4’-neolignan-9’-O-β-D-glucopyranoside (22), (7R,8R)-4,7,9,9’-tetrahydroxy-3,3’-dimethoxy-8-4’-oxyneolign-7’-ene-9’-O-β-D-glucopyranoside(23), (8S,7’S,8’R)-4,4’,9’-trihydroxy-3,3’-dimethoxy-7’,9-epoxylignan-7-oxo-4-O-β-D-glucopyranoside (24*), (8S,7’S,8’R)-4,4’,9’-trihydroxy-3,3’-dimethoxy-7’,9-epoxylignan-7-oxo-4’-O-β-D-glucopyranoside (25), (7R,8S)-dihydrode-hydrodiconiferyl alcohol-7’-oxo-4-O-β-D-glucopyranoside (26*),(7S,8R)-dihydrode-hydrodiconiferyl alcohol-4-O-β-D-glucopyranoside (27), (7S,8R,7’R,8’R)-pinoresinol-4,4’-di-O-β-D-glucopyrano-side (28), (7S,8R,7’R,8’R)-epipinoresinol-4’-O-β-D-glucopyranoside (29), secoisolariciresinol-4-O-β-D-glucopyranoside (30), arctiisesquineolignan A (31*), arctiisesquineolignan B (32*),lappaol H (33), 1-O-β-D-xylosfuranosyl-(1→6)-O-β-D-glucopyranosyl-4-hydroxy-3,5-dimethoxyphenol (34*), 1-O-β-D-xylopyranosyl-(1→6)-O-β-D-glucopyranoside-2-methoxy-4-hydroxyphenol (35),1-O-β-D-xylopyranosyl-(1→6)-O-β-D-glucopyranoside-3-methoxy-4-hydroxyphenol (36),4-O-β-D-xylopyrano-syl-(1→6)-O-β-D-glucopyranoside-4-hydroxy-3-methoxybenzyl alcohol (37),2-azanyl-8,9-dimethxyl-5H-purin-6-one (38),2’-deoxyguanosine (39), guanosine (40), thymine (41), thymine deoxyriboside (42),4-O-caffeoylquinic acid (43),3-O-caffeoylquinic acid (44),5-O-caffeoylquinic acid (45),3,5-di-O-caffeoylquinic acid (46), 4,5-di-O-caffeoylquinic acid (47), 1-ribityl-2,3-diketo-1,2,3,4-tetrahydro-6,7-dimethxyl-quinoxaline (48),tryptophan (49),3-benzyl-2,5-piperazinedione (50),2-phenethyl β-primeveroside (51) 0采用多种药理模型对牛蒡子的粗提物和单体化合物进行了活性筛选,发现牛蒡子乙醇提取物经乙酸乙酯萃取后的水部位,再经过大孔树脂以30%乙醇-水洗脱部位有很好的抑制Fe2+_半胱氨酸诱导的肝微粒体脂质过氧化活性和一定的抑制半乳糖胺诱导的WB-F344细胞损伤活性,95%乙醇-水洗脱部位显示有一定的抑制LPS刺激的小胶质细胞释放NO活性。单体化合物的药理筛选结果显示,化合物33和34*在剂量为1×10-5M时显示了较好的清除DPPH自由基活性(抑制率分别为50.07%和44.39%,阳性对照药抗坏血酸为44.00%),化合物11*和12*在剂量为2×10-5M时显示了与阳性对照药双环醇相当的抑制APAP诱导的HepG2细胞损伤活性(细胞存活率分别为53.89%和53.63%,阳性对照药双环醇为53.93%)。此外,化合物1*、3*、5*、11*和17*在剂量为1×10-5M时显示了较好的抑制LPS刺激的小胶质细胞释放NO活性(抑制率分别为96.34%、87.77%、63.31%、71.59%和66.67%,阳性对照药姜黄素的抑制率为53.00%)。同时所有单体化合物对HCT-8、 Be17402、BGC-823、A549和A2780细胞均不显示细胞毒作用。